This invention relates to introducers and to tube assemblies including an introducer.
Where a tube is to be introduced through an opening formed in the skin or other tissue, this may be done by first inserting a guide wire through the opening. An assembly of the tube with an introducer, such as an obturator inserted within it, is then slid along the guide wire. The guide wire and obturator are subsequently removed, leaving the tube in position. Examples of obturators are described, for example, in GB2316321, U.S. Pat. Nos. 4,246,897, 5,222,487 and GB2224213. The obturator typically has a nose with a pointed end protruding from the patient end of the tube. The nose is provided at the patient end of a strap, the machine end of which has a mount fitted with the machine end of the tube. The nose has a passage through which the guide wire extends, the passage opening through an aperture located centrally at the patient end and, at its opposite end, through an aperture displaced to one side of the strap, so that the passage is inclined away from the axis of the nose. The plane in which the patient end aperture lies extends at right angles to the axis of the nose and, therefore, at an angle to the guide wire passage. This arrangement means that, when the tube assembly is slid along the guide wire, the patient end surface of the obturator will meet the tissue surface at an angle. As a result of this, a potential tissue pinch point is created between the guide wire and one side of the obturator nose.